[FEA] Add justforkixes to the inventory

Request: The new server (justforkix0 and justforkix1) are installed and configured. They need to be added to the ansible inventory of SKAMPI.

Implementaion: Add both servers to the inventory file as the primary GPU servers

Testing:

• Run any provision description which uses NICs and GPUs on the servers
• Check results (e.g. spectrum in Grafana)